Answer:
Symbolism was an art movement in response to Realism and Impressionism. Poets, musicians, artists, and writers all used Symbolism to express meaning in an indirect manner. Symbolist painters wanted their pictures to depict a meaning beyond just the figures they drew.
Gustav Mahler would be my answer. Strauss was also composing during the late 19th and early 20th but Mahler created more of a fusion between the two.